Adjustable sheaves



Dec. 17, 1957 E, J, MccLosKEY 2,816,452

ADJUSTABLE SHEAVES 2 Sheets-Sheet 1 Filed May 29. 1956 JNVENTom ATTORNEYS Dec. 17, 1957 E. J. MGcLdsKl-:Y 2,816,452

ADJUSTABLE sHEAvEs Filed May 29, 1956 2 Sheets-Sheet 2 INVENToR: EI/swa cZ/la/'ey, BY .l e

ATTORNEYS United States Patent O ADJUSTABLE SHEAVES Ellsworth J. McCloskey, Norristown, Pa., assigner to The American Pulley Company, Philadelphia, Pa., a corporation of Pennsylvania Application May 29, 1956, Serial No. 588,087 2 Claims. (Cl. 74-230.17)

This invention relates to adjustable sheaves. Amongst the aims of my invention are to simplify the cons-truction of such sheaves; 'to provide improved facilities for relatively adjusting the belt-engaging disk components; and also to provide improved means which can be relied upon to secure the disk components against the possibility of accidental displacement in adjusted positions.

Other objects .and attendant advantages will appear from the following detailed description of the attached drawings, wherein:

Fig. l is a staggered axial section of an adjustable sheave conveniently embodying my invention, the section being taken .as indicated by the angled arrows I-I in Fig. 2.

Fig. 2 is a fragmentary elevational as seen from the right of Fig. 1.

Fig. 3 is a sectional view corresponding to Fig. 1 but with the belt-engaging disk components of the sheave differently adjusted.

Fig. 4 is a fragmentary view in transverse section taken as indicated by the angled arrows IV-IV in Fig. 3.

Fig. 5 is a fragmentary 1detail view in section taken as indicated by the angled arrows V-V in Fig. 2.

Fig. 6 and 7 are perspective views respectively of a sleeve :and a bushing embodied in the sheave.

As herein illustrated, the sheave of my invention comprises a tapered bushing 1 which has a flange 2 at one end thereof, said bushing being longitudinally split as at 3 (see Figs. 4 and 6) and axially bored to fit about the shaft 4 upon which the sheave is mounted, it being fixed against rotation relative to the shaft by a key designated S. Engaged over the bushing 1 is Ia sleeve 6 which is taperingly bored oomplementally and split longitudinally as at 7 `see Figs. 4 and 7, and which has a circumferential flange 8 at the end thereof remote from the flange 2 of the bushing 1. The outer surface of the sleeve 6 is cylindrical, and surrounding it, in turn, with capacity for being adjusted toward and away from each other, are two belt-engaging disk components 9 and 10 of which the beveled faces confront each other. A spline 11, engaged in key way 12 in the outer surface of the sleeve 6 and in registering key ways 13 and 14 (see Figs. 4 and 5) respectively in the bore of the disk components 9 and 10, serves to prevent rotation of these parts relative to each other.

The adjusting screw designated 15 passes freely through an aperture 16 in the flange 8 of the sleeve 6, and is held `aga-inst axial shifting relative to flange by .a polygonal end head 17 and .a stop collar 18 thereon which respec- -tively engage the outer and inner faces of said flange. The oppositely threaded portions 19 and 20 of the adjusting screw 15 are engaged in correspondingly tapped holes 21 and 22 in the respective disk components 9 and 10.

Displacement of the disk components 9 and 10 in view of the sheave Nice adjusted position is prevented by a pair of locking screws 25 which, see Figs. 2 and 4, are circumferentially spaced from the adjusting screw 15. As shown, Ithe locking screws 25 pass freely through apertures 26 in the flange 8 of the sleeve 6 and also through aligned clearance holes 27 and 28 respectively in the disk components 9 and 10, the distal Ith-readed end of said screws engaging in complementally tapped holes 29 in the flange 2 of the bushing 1. Like the adjusting screw 15, each locking screw 25 is held against shifting axially relative to the flange 8 of the sleeve 6 by virtue of being provided with an end head 30 anda stop collar 31 for respectively engaging the outer and inner faces of said flange. From Fig. 3 it will be observed, that the disk component 10 has, in its outer face, an axial recess or counterbore 32 for clearance of the collars 18 and 31 respectively of the adjusting and locking screws 15 and 25 when the two disk components are adjusted to the maximum extent away from each other.

To adjust the sheave, the locking screws 25 are backed off slightly whereby -the wedging action between the bushing 1 and the sleeve 6 is eased and the disk components 9 and 10 are relieved of restraint so that they can be shifted along said sleeve. With this accomplished, the adjusting screw 15 is turned clockwise in Fig. 1 with attendant separation of the disk componen-ts by the reverse action of the differential threads 21 and 22 of said screw. After the desired adjustment is attained, the locking screws 25 are re-tightened `to draw the bushing 1 and the sleeve 6 axially in a direction toward each other, the bushing being thereby circumferentially contracted and the sleeve circumferentially expanded within the disk components 9 and 10. As a result of this improved construction, it will be seen that the disk components are effectively secured against the possibility of displacement in adjusted positions by pull of the belt (not illustrated) during operation of sheave.

Having thus described my invention, I claim:

1. In an adjustable sheave, a tapered bushing bored to fit `about a shaft upon which the sheave is mounted and lhaving a `circumferential flange at one end thereof; an internally tapered split sleeve fitting about the bushing and having a flange at the end thereof opposite to the flanged end of the bushing, the outer surface of the sleeve being cylindrical; a pair of belt engaging risk components surrounding and shiftable relative to each other along the sleeve, and respectively having beveled faces confronting each other; `an adjusting screw constrained to rotation in the flange of the sleeve and having oppositely pitched threaded portions engaged in correspondingly tapped holes in the respective disk components; and at least one locking screw constrained to rotation in the flange of the sleeve, said screw passing through aligned clearance holes in the two disk components and threadedly engaging a tapped hole in the flange of the bushing.

2. An adjustable sheave according to claim 1, wherein one of the disk components has an axial recess or counterbore in ilts outer face to clear the stop collars of the Iadjust-ing and locking screws when the two disk components areadjusted to the maximum extent away from each other.

References Cited in the file of this patent UNITED STATES PATENTS 

